Presently, the global food system faces a crises of unprecedented scale as a result of four simultaneously colliding dilemmas, all arising from a relatively recent pattern of dependence on rapidly depleting petroleum. Specifically, higher oil prices has resulted in increased costs for tractor fuel, agricultural chemicals and the transport of farm inputs and outputs. In turning to alternative fuel sources, biofuels result in farm land conversion from food production to fuel production, thus making food more costly. The burning of petroleum fuels causes green house gas emissions leading to less predictable food production. Finally, is the degradation of essential resources such as top soil, fresh water and farming skills resulting from unsustainable methods of production stimulated by decades of relatively inexpensive energy.
Replacing agricultural tractors previously powered by internal combustion engines with electric tractors and, ideally, those electric tractors that are powered by rechargeable batteries which integrate with solar cells has the potential to reduce or eliminate the negative impacts of petroleum dependence. Specifically, the cost of operating a solar electric tractor will not be affected by oil depletion. Solar electric tractors do not depend on the combustion of liquid fuels so that farmland can remain in food production. Solar electric tractors further are zero emission vehicles so that their use will not produce green house gases that cause climate change. Sustainable small farms will replace large scale agribusiness because large fuel intensive machinery will become unaffordable as fuel prices increase. The optimum solar electric tractor is limited only by the amount of energy that can be stored in batteries or generated by solar arrays so the unsustainable energy intensive production methods employed previously will be replaced by serving local markets. A further collateral benefit is that the constant maintenance, noise and pollution associated with gas and diesel tractors, being both a nuisance and health hazard would be eliminated.
In dealing with tractors employing internal combustion engines, the maintenance and upkeep issues inherent in such modes of transportation are eliminated by moving to solar electric tractors. In doing so, one need not be concerned with maintaining an internal combustion engine in optimal and efficient condition. Failure to do so results in idling and stalling problems. No longer does one need be concerned with coolant, oil and filter changes, oil leaks, pollution which is normally dangerous to breath but can affect crops. By contrast, solar electric tractors require low maintenance and are resultingly low in operating costs. They are clean and quiet to operate and are 5 to 10 times more energy efficient than internal combustion engines. Such vehicles can be charged from onsite renewable energy sources. As will be more fully developed in the present application, battery weight can be employed beneficially to counter balance loads imposed upon the tractor as well as to lower the tractor's center of gravity. Electric motors produce higher torque at low speed which is ideal for tractor operation. When individual motors are used on multiple drive wheels, a joy stick can be employed providing a zero radius steering capability. Separate power take off motors can also be employed to increase performance.
It is thus an object of the present invention to provide an electric tractor, and preferably, a solar powered electric tractor which eliminates the limitations imposed upon tractors when employing internal combustion engines.
It is yet a further object of the present invention to provide a frame and geometry for an electric tractor in which battery placement is flexible and can be employed to lower the tractor's center of gravity and act as a counter balance thus eliminating the need for the purchase and installation of dead weight to accomplish these purposes.
These and further objects will be more readily apparent when considering the following disclosure and appended claims.